Re: sendmail 8.18.1 MFC'ed to stable/13 and stable/14

From: Miroslav Lachman <000.fbsd_at_quip.cz>
Date: Thu, 08 Feb 2024 10:06:54 UTC
On 07/02/2024 20:02, mike tancsa wrote:
> Thanks for the continued sendmail support!   One question, I noticed the 
> new mc file makes the following changes which refers to a file that does 
> not normally exist on RELENG_13.  What is the best way to generate that 
> file ?

[..]

> @@ -606,7 +607,7 @@
>   # Directory containing hashes pointing to certificate revocation 
> status files
>   #O CRLPath
>   # DHParameters (only required if DSA/DH is used)
> -#O DHParameters
> +O DHParameters=/etc/mail/certs/dh.param


Almost any network daemon today can use DHParams files, but each have 
it's own location and some of them provide the script to re-generate it 
periodically. There was a PR about it for ProFTPD few years ago:

https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=208953

As a quick POC, I've provided a simple dhparams_gen.sh script.
https://bugs.freebsd.org/bugzilla/attachment.cgi?id=247526&action=edit

I thing something like this can be included in the base and all services 
from ports and base should be configured to use the same dhparams.pem 
file easily managed from cron, or manually by one simple command.

The submitted script generates DH params from 1024 to 8192. From what I 
read on the net, 1024 and 1536 should not be used and from my experience 
generating anything above 4096 takes too much time (the script runs for 
hours on a not so modern machine) so I created another version of the 
dhparams_gen.sh where user can specify what sizes will be generated by 
defining the range, for example "2048 4096" will generate only 2048 3072 
4096 sizes.
It is very simple scripting and as nobody reacted to the PR I didn't 
post the newer version. I can send it to you I you want.

Kind regards
Miroslav Lachman